Insight | Challenges ahead for £1bn Silvertown Tunnel

After seven months of uncertainty the government has finally given the green light to the much-delayed £1bn East London Silvertown Tunnel scheme. However, despite finally getting the go-ahead, the project still faces a number of challenges in the coming months and years ahead.

Licencing problems

Several conditions were attached to the development consent order (DCO) when it was granted by transport secretary Chris Grayling, which Transport for London (TfL) will have to meet before the tunnel opens in 2021.

While it is not unusual for big infrastructure schemes to have conditions attached to a DCO, there is one condition that could put the brakes on the Silvertown Tunnel progressing.

The condition concerns a nearby chemical plant called Brenntag Inorganic Chemicals which is close to the 1km, twin-bore road tunnel.

Under the conditions of the DCO, a chemicals licence for the plant must be modified or revoked before the tunnel can open to stop or change production at the plant and prevent danger to the public using the tunnel.

Getting the licence could take some time and delay the scheme, which Grayling acknowledged when he gave the go-ahead.

As law firm Burges Salmon partner Liz Dunn explains, the risk of delay “adds a bit of complexity” to the private finance element of the scheme, which would be built under a design, construct, finance and maintain contract and partly funded though a toll.

“They [the winning bidder] will have to think carefully, and I’m sure they will be very up to speed on this, about which risks they are prepared to take on, and which risks they say should sit with government in terms of delay,” she says.

“So it’s how far TfL take this project in terms of discharging the requirements [of the DCO] and how much of that actually sits with the contractor, and there will be certain things that I think the contractor will say, ‘we can’t take that risk, it’s got to sit with government’. So that will be an interesting dynamic which plays out there.”

Ferrovial-owned Cintra Global and Hochtief are still in the race to win the contract, which TfL expects to award in spring 2019, after a Skanska/Straberg joint venture pulled out in March.

Environmental worries

Pollution modelling for the scheme shows that while the tunnel would make air quality better in some places, it would make pollution worse in other areas. TfL argues that the tunnel will comply with European air pollution requirements as the deterioration falls within accepted limits.

But FoE argues that a deterioration in air quality anywhere in the city is unacceptable for residents. Air quality is a pressing issue: just two days ago (Tuesday 21 May) the government was criticised by campaigners over its “hugely dissapointing” new clean air strategy, while last week the UK was referred to the European Court of Justice for its failure to properly tackle air pollution.

FoE air quality campaigner Jenny Bates warned the group would continue to oppose the scheme.

“It isn’t OK that somewhere being made worse is being acceptable just because there’s elsewhere in the zone even worse,” she said.

“There will be quite a lot of consideration [of the DCO] and who knows what steps might be taken?”

But business campaign group London First infrastructure director David Leam said the concerns should be considered within the context of the scheme.

“This isn’t the start of some major new road building programme for London, this isn’t the first of many big, new motorways smashing through the centre of the city; it’s a one-off bit of new road infrastructure to address a very specific local problem,” he said.

“Additional river crossings in the east have been identified as a gap in London’s infrastructure for well over 50 years, so it’s high time they were plugged.”

Councils’ concerns

TfL faces a challenge to get support from the two boroughs which would host the 1km, twin-bore tunnel. Both the Royal Borough of Greenwich (RBG) and Newham Council have expressed concerns over the negative impact of the scheme on air quality in the areas.

As soon as the DCO was granted, Newham mayor Rokhsana Fiaz called for the scheme to be scrapped and said she would pressure government to find an alternative scheme.

She said: “London already faces significant problems with air quality. In Newham alone 96 deaths a year are attributed to air quality related illnesses compounding health inequalities. This tunnel will only make air quality in the borough worse”

Although the response to the tunnel has been less extreme in Greenwich, the £1bn scheme has not been greeted with enthusiasm. RBG has said while it agrees more river crossings are needed in East London, other public transport schemes such as a London Overground extension and a DLR link to Thamesmead are “essential”.

A spokesperson for RBG said: “RBG is examining the DCO following the Secretary of State’s decision, in particular we are looking at how the proposals would affect the borough and are formulating our response.”

The Silvertown Tunnel will connect Greenwich and Silvertown, just east of the Blackwall Tunnel (which will also be tolled as a result of the Silvertown Tunnel to manage traffic demand). It will be built in an area historically used by heavy industry with remnants of old structures still in place, pointing to significant engineering challenges for the project further down the line.

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